<?php
class Generate_code
{   
    var $name = 'test';

    public function getUID()
    {
        $uuid_v4 = Generate_code::gen_uuid();
        $uuid_v5 = Generate_code::uuid5($uuid_v4,$this->name);
        return $uuid_v5;  
    }

    public static function gen_uuid() {
        
        return sprintf( '%04x%04x-%04x-%04x-%04x-%04x%04x%04x',
            // 32 bits for "time_low"
            mt_rand( 0, 0xffff ), mt_rand( 0, 0xffff ),

            // 16 bits for "time_mid"
            mt_rand( 0, 0xffff ),

            // 16 bits for "time_hi_and_version",
            // four most significant bits holds version number 4
            mt_rand( 0, 0x0fff ) | 0x4000,

            // 16 bits, 8 bits for "clk_seq_hi_res",
            // 8 bits for "clk_seq_low",
            // two most significant bits holds zero and one for variant DCE1.1
            mt_rand( 0, 0x3fff ) | 0x8000,

            // 48 bits for "node"
            mt_rand( 0, 0xffff ), mt_rand( 0, 0xffff ), mt_rand( 0, 0xffff )
        );
    }

    public static function uuid5($namespace, $name) 
    {
        
        if(!self::is_valid($namespace)) return false;

        // Get hexadecimal components of namespace
        $nhex = str_replace(array('-','{','}'), '', $namespace);

        // Binary Value
        $nstr = '';

        // Convert Namespace UUID to bits
        for($i = 0; $i < strlen($nhex); $i+=2) 
        {
            $nstr .= chr(hexdec($nhex[$i].$nhex[$i+1]));
        }

        // Calculate hash value
        $hash = sha1($nstr . $name);

        return sprintf('%08s-%04s-%04x-%04x-%12s',

        // 32 bits for "time_low"
        substr($hash, 0, 8),

        // 16 bits for "time_mid"
        substr($hash, 8, 4),

        // 16 bits for "time_hi_and_version",
        // four most significant bits holds version number 5
        (hexdec(substr($hash, 12, 4)) & 0x0fff) | 0x5000,

        // 16 bits, 8 bits for "clk_seq_hi_res",
        // 8 bits for "clk_seq_low",
        // two most significant bits holds zero and one for variant DCE1.1
        (hexdec(substr($hash, 16, 4)) & 0x3fff) | 0x8000,

        // 48 bits for "node"
        substr($hash, 20, 12)
        );
    }

    public static function is_valid($uuid) {
        return preg_match('/^\{?[0-9a-f]{8}\-?[0-9a-f]{4}\-?[0-9a-f]{4}\-?'.
                      '[0-9a-f]{4}\-?[0-9a-f]{12}\}?$/i', $uuid) === 1;
    }


}